- From: Dobbs, Brooks <bdobbs@doubleclick.net>
- Date: Wed, 22 Oct 2003 15:31:48 -0400
- To: "'public-p3p-spec@w3.org'" <public-p3p-spec@w3.org>
- Message-ID: <D464F551A951ED4E804B9713B519E6C9029418AE@NYC-EX101.doubleclick.net>
Though I have enormous sympathy for the issue we are trying to resolve here. I have some concerns with the mechanism suggested. They are in no particular order: 1) We need be careful between providing tools on which to make policy and making policy itself. While it may be a useful tool to have the ability to state that collection covered by separate PRFs is under the control of the same entity, ultimately it is up to the UAs to decide how they want to implement these tools. 2) We use the term entity (and later in the agent relationship proposal - "agent") without providing sufficient guidance on what this means. Rigo suggests there may be ways around this but I think they would be unclear at best and difficult to explain to the end user. This suggests to me that point 1) may mean that UAs don't act on this tool if they had it. 3) I think that there is an issue in that entity is today defined at the policy level. A PRF for a host can reference 2 distinct policies each of 2 distinct entities (data controllers) - how then can there be meaning to say at the PRF level this entity is the same as anything else? The same as which of the 2? 4) There would need to be a mechanism to expire same entity relationship. This may be handled through the expiry in policy files but there is currently no such mechanism for CPs 5) Headers are limited practically by the number of same hosts that they can declare. Also declaring multiple "same-entity" relationships would presumably require a validation against each full policy prior to accepting the accuracy of the header declaration. This is somewhat illogical, as, IF we where to accept the performance hit of policy prefetching, then we would have no need for CPs! Jack rightly points out that we may only need to validate against the PRF and not the policy - but I think that I may have brought that into question with point 3). 6) Again on the topic of CPs, once a same entity relationship has been established between cookie (set by A) and site B from which an asset appears, how they can a same entity relationship be established from a subsequent replay on site C (provided that PRFs or policies) for all these sites do indeed declare each other as same entity? Sorry to be so elaborate here. Again I am completely sympathetic - just not sure we are there yet or if I see a clear way through the issues. Thanks, Brooks Brooks Dobbs Director of Privacy Technology DoubleClick, Inc. email: bdobbs@doubleclick.net <mailto:bdobbs@doubleclick.net> office: 404.995.6634
Received on Wednesday, 22 October 2003 15:31:54 UTC